Class | MCollective::Message |
In: |
lib/mcollective/message.rb
|
Parent: | Object |
container for a message, its headers, agent, collective and other meta data
VALIDTYPES | = | [:message, :request, :direct_request, :reply] |
agent | [RW] | |
collective | [RW] | |
discovered_hosts | [RW] | |
expected_msgid | [R] | |
filter | [RW] | |
headers | [RW] | |
message | [R] | |
msgtime | [R] | |
options | [RW] | |
payload | [R] | |
reply_to | [R] | |
request | [R] | |
requestid | [RW] | |
ttl | [RW] | |
type | [R] | |
validated | [R] |
payload - the message body without headers etc, just the text message - the original message received from the middleware options[:base64] - if the body base64 encoded? options[:agent] - the agent the message is for/from options[:collective] - the collective its for/from options[:headers] - the message headers options[:type] - an indicator about the type of message, :message, :request, :direct_request or :reply options[:request] - if this is a reply this should old the message we are replying to options[:filter] - for requests, the filter to encode into the message options[:options] - the normal client options hash options[:ttl] - the maximum amount of seconds this message can be valid for options[:expected_msgid] - in the case of replies this is the msgid it is expecting in the replies
# File lib/mcollective/message.rb, line 22 22: def initialize(payload, message, options = {}) 23: options = {:base64 => false, 24: :agent => nil, 25: :headers => {}, 26: :type => :message, 27: :request => nil, 28: :filter => Util.empty_filter, 29: :options => {}, 30: :ttl => 60, 31: :expected_msgid => nil, 32: :collective => nil}.merge(options) 33: 34: @payload = payload 35: @message = message 36: @requestid = nil 37: @discovered_hosts = nil 38: @reply_to = nil 39: 40: @type = options[:type] 41: @headers = options[:headers] 42: @base64 = options[:base64] 43: @filter = options[:filter] 44: @expected_msgid = options[:expected_msgid] 45: @options = options[:options] 46: 47: @ttl = @options[:ttl] || Config.instance.ttl 48: @msgtime = 0 49: 50: @validated = false 51: 52: if options[:request] 53: @request = options[:request] 54: @agent = request.agent 55: @collective = request.collective 56: @type = :reply 57: else 58: @agent = options[:agent] 59: @collective = options[:collective] 60: end 61: 62: base64_decode! 63: end
# File lib/mcollective/message.rb, line 107 107: def base64_decode! 108: return unless @base64 109: 110: @payload = SSL.base64_decode(@payload) 111: @base64 = false 112: end
# File lib/mcollective/message.rb, line 114 114: def base64_encode! 115: return if @base64 116: 117: @payload = SSL.base64_encode(@payload) 118: @base64 = true 119: end
# File lib/mcollective/message.rb, line 197 197: def create_reqid 198: Digest::MD5.hexdigest("#{Config.instance.identity}-#{Time.now.to_f}-#{agent}-#{collective}") 199: end
# File lib/mcollective/message.rb, line 141 141: def decode! 142: raise "Cannot decode message type #{type}" unless [:request, :reply].include?(type) 143: 144: @payload = PluginManager["security_plugin"].decodemsg(self) 145: 146: if type == :request 147: raise 'callerid in request is not valid, surpressing reply to potentially forged request' unless PluginManager["security_plugin"].valid_callerid?(payload[:callerid]) 148: end 149: 150: [:collective, :agent, :filter, :requestid, :ttl, :msgtime].each do |prop| 151: instance_variable_set("@#{prop}", payload[prop]) if payload.include?(prop) 152: end 153: end
# File lib/mcollective/message.rb, line 125 125: def encode! 126: case type 127: when :reply 128: raise "Cannot encode a reply message if no request has been associated with it" unless request 129: raise 'callerid in original request is not valid, surpressing reply to potentially forged request' unless PluginManager["security_plugin"].valid_callerid?(request.payload[:callerid]) 130: 131: @requestid = request.payload[:requestid] 132: @payload = PluginManager["security_plugin"].encodereply(agent, payload, requestid, request.payload[:callerid]) 133: when :request, :direct_request 134: @requestid = create_reqid 135: @payload = PluginManager["security_plugin"].encoderequest(Config.instance.identity, payload, requestid, filter, agent, collective, ttl) 136: else 137: raise "Cannot encode #{type} messages" 138: end 139: end
in the case of reply messages we are expecting replies to a previously created message. This stores a hint to that previously sent message id and can be used by other classes like the security plugins as a means of optimizing their behavior like by ignoring messages not directed at us.
# File lib/mcollective/message.rb, line 102 102: def expected_msgid=(msgid) 103: raise "Can only store the expected msgid for reply messages" unless @type == :reply 104: @expected_msgid = msgid 105: end
publish a reply message by creating a target name and sending it
# File lib/mcollective/message.rb, line 179 179: def publish 180: Timeout.timeout(2) do 181: # If we've been specificaly told about hosts that were discovered 182: # use that information to do P2P calls if appropriate else just 183: # send it as is. 184: if @discovered_hosts && Config.instance.direct_addressing 185: if @discovered_hosts.size <= Config.instance.direct_addressing_threshold 186: @type = :direct_request 187: Log.debug("Handling #{requestid} as a direct request") 188: end 189: 190: PluginManager["connector_plugin"].publish(self) 191: else 192: PluginManager["connector_plugin"].publish(self) 193: end 194: end 195: end
Sets a custom reply-to target for requests. The connector plugin should inspect this when constructing requests and set this header ensuring replies will go to the custom target otherwise the connector should just do what it usually does
# File lib/mcollective/message.rb, line 91 91: def reply_to=(target) 92: raise "Custom reply targets can only be set on requests" unless [:request, :direct_request].include?(@type) 93: 94: @reply_to = target 95: end
Sets the message type to one of the known types. In the case of :direct_request the list of hosts to communicate with should have been set with discovered_hosts else an exception will be raised. This is for extra security, we never accidentally want to send a direct request without a list of hosts or something weird like that as it might result in a filterless broadcast being sent.
Additionally you simply cannot set :direct_request if direct_addressing was not enabled this is to force a workflow that doesnt not yield in a mistake when someone might assume direct_addressing is enabled when its not.
# File lib/mcollective/message.rb, line 74 74: def type=(type) 75: if type == :direct_request 76: raise "Direct requests is not enabled using the direct_addressing config option" unless Config.instance.direct_addressing 77: 78: unless @discovered_hosts && !@discovered_hosts.empty? 79: raise "Can only set type to :direct_request if discovered_hosts have been set" 80: end 81: end 82: 83: raise "Unknown message type #{type}" unless VALIDTYPES.include?(type) 84: 85: @type = type 86: end
Perform validation against the message by checking filters and ttl
# File lib/mcollective/message.rb, line 156 156: def validate 157: raise "Can only validate request messages" unless type == :request 158: 159: msg_age = Time.now.utc.to_i - msgtime 160: 161: if msg_age > ttl 162: cid = "" 163: cid += payload[:callerid] + "@" if payload.include?(:callerid) 164: cid += payload[:senderid] 165: 166: if msg_age > ttl 167: PluginManager["global_stats"].ttlexpired 168: 169: raise(MsgTTLExpired, "Message #{requestid} from #{cid} created at #{msgtime} is #{msg_age} seconds old, TTL is #{ttl}") 170: end 171: end 172: 173: raise(NotTargettedAtUs, "Received message is not targetted to us") unless PluginManager["security_plugin"].validate_filter?(payload[:filter]) 174: 175: @validated = true 176: end